They would have to chemically, and physically, separate out the epoxy, or polyester resins, which constitute anywhere from about 25 to 75% of the composite.
Well, yea. That is a part of the process. As I understand it, the recycling begins with grinding the carbon fiber product to a rather small size. Exactly what is done to purge the epoxy I do not know, but I have seen recycled carbon fiber listed for sale with some detailed notes (sorry, I do not remember where as it was quite some time ago and I was not interested in the recycled stuff) about the difference in fiber length, strength and so on.
In a quality fabrication the % of epoxy is a lot less than most people would expect. Vacuum bagging and so on allows for the minimizing of unnecessary epoxy that adds nothing but excess weight.
Well, yea. That is a part of the process. As I understand it, the recycling begins with grinding the carbon fiber product to a rather small size. Exactly what is done to purge the epoxy I do not know, but I have seen recycled carbon fiber listed for sale with some detailed notes (sorry, I do not remember where as it was quite some time ago and I was not interested in the recycled stuff) about the difference in fiber length, strength and so on.
In a quality fabrication the % of epoxy is a lot less than most people would expect. Vacuum bagging and so on allows for the minimizing of unnecessary epoxy that adds nothing but excess weight.
They need solvents to remove polyester and epoxy, so we're back to the environmental effects of the waste there. I'm also not sure as to the resultant purity of the finalized product.
One of the main features of carbon fiber, or course, is the fact that the fibers are as long as the product sheet itself. The very short fibers of the recycled product has only a much more limited usefulness.
I wonder how the cost of recovery can be charged back in the sale price of the limited use recycled product.
Raise your hands if you're a Material Science Engineer or Mechanical Engineer, or Chemical Engineer.
This discussion is truly a hack conversation of duct taped pieces of information.
I truly look forward to the pearls of wisdom if we ever have to discuss Tribology or MEMS.
I love reading about references to Fracture Mechanics from folks who haven't the acumen to have studied it.
Ah, actually, I do come at least close to that. Four years of chemistry in college. Four years of physics, and fours years of courses in mechanical and electronics engineering. Also seven years designing electrical, electronic and mechanical systems, and 28 years working with complex chemical production lines.
Also, continued membership in the AAAS and Academy of Sciences, following developments in the journals.
There are a few issues raised in this thread that need clearing up.
No. 1 - Recycling
Contrary to popular belief, Carbon Fibre composites can be recycled. Thanks to innovations at Recycled Carbon Fibre Ltd (part of the Milled Carbon Group), processes have been developed to remove resin (the thermoset or thermoplastic part) and use the reclaimed Carbon fabric as if it were virgin product.
No. 2 - Aesthetic Finish
Despite loving Carbon Fibre myself, I do think that Apple has done the right thing to try to hide the material, even if only partially. I think Apple have always done a great job at styling and I actually prefer an aluminium finish to Carbon Fibre finish (on laptops at least). They could, if they were to be really adventurous, apply aluminium on the visible layer using either induction welding, or high strength glue, probably epoxy.
There are a few issues raised in this thread that need clearing up.
[INDENT]No. 1 - Recycling
Contrary to popular belief, Carbon Fibre composites can be recycled. Thanks to innovations at Recycled Carbon Fibre Ltd (part of the Milled Carbon Group), processes have been developed to remove resin (the thermoset or thermoplastic part) and use the reclaimed Carbon fabric as if it were virgin product.
I never said it couldn't be recycled, just that it wasn't done much, that it was expensive, that the materials had a much more limited usefulness due to the short fibers, and there was the question of what happened to the waste from the epoxy, polyester etc resins and solvents used to remove them.
This company claims to be the only commercially sized reclaimer of this, and it's capacity is 2,000 tons of waste a year. I don't know if it actually DOES 2,000 tons a year.
That's a drop in the bucket. That likely leaves 99.9% un-recycled.
This company claims to be the only commercially sized reclaimer of this, and it's capacity is 2,000 tons of waste a year. I don't know if it actually DOES 2,000 tons a year.
That's a drop in the bucket. That likely leaves 99.9% un-recycled.
They probably do, as companies such as Boeing, Airbus etc want their recycling credentials up, and Recycled Carbon Fibre Ltd taking it off their hands counts. Companies like Boeing use the recyclate in less-structural (though it has properties very close to that of virgin Carbon) parts of the aircraft.
Quote:
Originally Posted by melgross
much more limited usefulness due to the short fibers
The short fibres are ideal for injection moulding, and also for EMI shielding on houses under electricity pylons and stuff.
They probably do, as companies such as Boeing, Airbus etc want their recycling credentials up, and Recycled Carbon Fibre Ltd taking it off their hands counts. Companies like Boeing use the recyclate in less-structural (though it has properties very close to that of virgin Carbon) parts of the aircraft.
I'd still like to know what they do with the resin/solvent residue. I'm not impressed with recycling a material until I know what is being don with the rest of it.
Quote:
The short fibres are ideal for injection moulding, and also for EMI shielding on houses under electricity pylons and stuff.
Comments
They would have to chemically, and physically, separate out the epoxy, or polyester resins, which constitute anywhere from about 25 to 75% of the composite.
Well, yea. That is a part of the process. As I understand it, the recycling begins with grinding the carbon fiber product to a rather small size. Exactly what is done to purge the epoxy I do not know, but I have seen recycled carbon fiber listed for sale with some detailed notes (sorry, I do not remember where as it was quite some time ago and I was not interested in the recycled stuff) about the difference in fiber length, strength and so on.
In a quality fabrication the % of epoxy is a lot less than most people would expect. Vacuum bagging and so on allows for the minimizing of unnecessary epoxy that adds nothing but excess weight.
Well, yea. That is a part of the process. As I understand it, the recycling begins with grinding the carbon fiber product to a rather small size. Exactly what is done to purge the epoxy I do not know, but I have seen recycled carbon fiber listed for sale with some detailed notes (sorry, I do not remember where as it was quite some time ago and I was not interested in the recycled stuff) about the difference in fiber length, strength and so on.
In a quality fabrication the % of epoxy is a lot less than most people would expect. Vacuum bagging and so on allows for the minimizing of unnecessary epoxy that adds nothing but excess weight.
They need solvents to remove polyester and epoxy, so we're back to the environmental effects of the waste there. I'm also not sure as to the resultant purity of the finalized product.
One of the main features of carbon fiber, or course, is the fact that the fibers are as long as the product sheet itself. The very short fibers of the recycled product has only a much more limited usefulness.
I wonder how the cost of recovery can be charged back in the sale price of the limited use recycled product.
This discussion is truly a hack conversation of duct taped pieces of information.
I truly look forward to the pearls of wisdom if we ever have to discuss Tribology or MEMS.
I love reading about references to Fracture Mechanics from folks who haven't the acumen to have studied it.
Raise your hands if you're a Material Science Engineer or Mechanical Engineer, or Chemical Engineer.
This discussion is truly a hack conversation of duct taped pieces of information.
I truly look forward to the pearls of wisdom if we ever have to discuss Tribology or MEMS.
I love reading about references to Fracture Mechanics from folks who haven't the acumen to have studied it.
Ah, actually, I do come at least close to that. Four years of chemistry in college. Four years of physics, and fours years of courses in mechanical and electronics engineering. Also seven years designing electrical, electronic and mechanical systems, and 28 years working with complex chemical production lines.
Also, continued membership in the AAAS and Academy of Sciences, following developments in the journals.
Does any of that count?
There are a few issues raised in this thread that need clearing up. (Rant Over)
Greg
Hi All,
There are a few issues raised in this thread that need clearing up.
[INDENT]No. 1 - Recycling
Contrary to popular belief, Carbon Fibre composites can be recycled. Thanks to innovations at Recycled Carbon Fibre Ltd (part of the Milled Carbon Group), processes have been developed to remove resin (the thermoset or thermoplastic part) and use the reclaimed Carbon fabric as if it were virgin product.
I never said it couldn't be recycled, just that it wasn't done much, that it was expensive, that the materials had a much more limited usefulness due to the short fibers, and there was the question of what happened to the waste from the epoxy, polyester etc resins and solvents used to remove them.
This company claims to be the only commercially sized reclaimer of this, and it's capacity is 2,000 tons of waste a year. I don't know if it actually DOES 2,000 tons a year.
That's a drop in the bucket. That likely leaves 99.9% un-recycled.
This company claims to be the only commercially sized reclaimer of this, and it's capacity is 2,000 tons of waste a year. I don't know if it actually DOES 2,000 tons a year.
That's a drop in the bucket. That likely leaves 99.9% un-recycled.
They probably do, as companies such as Boeing, Airbus etc want their recycling credentials up, and Recycled Carbon Fibre Ltd taking it off their hands counts. Companies like Boeing use the recyclate in less-structural (though it has properties very close to that of virgin Carbon) parts of the aircraft.
much more limited usefulness due to the short fibers
The short fibres are ideal for injection moulding, and also for EMI shielding on houses under electricity pylons and stuff.
Greg
They probably do, as companies such as Boeing, Airbus etc want their recycling credentials up, and Recycled Carbon Fibre Ltd taking it off their hands counts. Companies like Boeing use the recyclate in less-structural (though it has properties very close to that of virgin Carbon) parts of the aircraft.
I'd still like to know what they do with the resin/solvent residue. I'm not impressed with recycling a material until I know what is being don with the rest of it.
The short fibres are ideal for injection moulding, and also for EMI shielding on houses under electricity pylons and stuff.
Greg
Still, fewer uses.